Sheet stacker



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g- 1964 J. A. MILLER ETAL SHEET STACKER 7 Sheets-Sheet 2 Filed Jan. 14, 1963 INVENTORS JOSEPH A. MILLER F'EHNK H. KRUGLJNSK! HTTOENEV vx w mrk Aug- 1 J. A. MILLER ETAL SHEET STACKER 7 Sheets-Sheet 3 Filed Jan. 14, 1965 INVENTORS JosaPH H. MlLLER m S m L V w M R K m A. T K H mm Y B Aug. 4, 1964 .1. A. MILLER ETAL 3,143,344

SHEET STACKER Filed Jan. 14, 1963 7 Sheets-Sheet 4 7 W I F] I I INVENTORS JOSEPH Q. MILLER YFEFINK H KRUGLINSKI HTTORNEV 1964 J. A. MILLER ETAL 3,143,344

SHEET STACKER Filed Jan. 14, 1963 7 Sheets-Sheet 5 IIHII| llllilI INVENTORS JOSEPH F). MILLER BY FRANK A. KEUGLINSKI Aug- 4, 1 J. A. MILLER ETAL SHEET STACKER 7 Sheets-Sheet 6 Filed Jan. 14, 1963 INVENTORS JOSEPH A MILLER FRHNK A KRUGLlNSKl l I II |l|L. -L l L ii- L EWE EE vl 1 MIN" W g 1964 .1. A. MILLER ETAL SHEET STACKER Filed Jan. 14, 1963 '7 Sheets-Sheet 7 INVENTORS '\/J;$EPH Q. MILL-BF? BYFEQNK A. KRUGLINSKI TTORNE Y United States Patent 3,143,344 SEEET STACKER Joseph A. Miller, Englewood, and Frank A. Kruglinski,

North Bergen, N.J., assignors to General Corrugated Machinery Co. Inc., Palisades Park, N.J., a corporation of New Jersey Filed Jan. 14, 1963, Ser. No. 251,207 17 Claims. (Cl. 27168) The invention relates to sheet stackers adapted for stacking sheets delivered from a printer-slotter to a pallet. In particular, the invention relates to such a sheet stacker which continues to run and permits the printer-slotter to continue to run while certain adjustments are made and stoppages are cleared.

It is an object of the invention to provide a sheet stacker wherein the flow of sheets from the sheet stacker onto the pallet may be stopped without the necessity of stopping the flow of sheets from the printer-slotter to the sheet stacker. It is a further object of the invention to provide such a sheet stacker wherein the flow of sheets to the pallet may be interrupted either manually or automatically. It is a still further object of the invention to provide a layboy between the printerslotter and the boom of the sheet stacker such that the end nearer the printer-slotter may be raised mechanically. It is also an object of the invention to provide such a layboy in which the hold-down straps, which are transversely movable on a bar carried on the layboy, overlay the belts and do not drop down between the belts when the feed of sheets from the printer-slotter is stopped.

These and other objects, advantages, features and uses will be apparent during the course of the following description when taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is an end elevational View of the delivery end of the sheet stacker of the invention;

FIGURES 2 and 2A join on the line AA and together are a side elevational view of the sheet stacker of FIGURE 1;

FIGURE 3 is an enlarged sectional view taken on the line 33 of FIGURE 1;

FIGURE 4 is an enlarged partial plan view of the feed end of the sheet stacker of FIGURE 1;

FIGURE 5 is a partial plan View of a portion of the layboy showing the fixed arm of the layboy;

FIGURE 6 is an enlarged partial plan view of the delivery end of the sheet stacker of FIGURE 1;

FIGURE 7 is a detailed view of the drive of the boom and layboy belts taken along the lines 77 of FIGURE 8, viewed in the direction of the arrows; and

FIGURE 8 is a sectional view along the lines 8-8 of FIGURE 7, viewed in the direction of the arrows.

The sheet stacker of the invention comprises three sections: the main frame, the movable boom section and the layboy section. The movable boom is pivotally mounted in the main frame and the delivery end moves upwards in a vertical line as the stack on the pallet rises. Suitable controls are provided to cause the boom to rise as required by the size of the stack. The feed end of the sheet stacker boom moves horizontally to compensate for the vertical movement of the delivery end. The layboy section is installed in a fixed position between the feed end of the boom section and the delivery end of the printerslotter and is employed to feed the sheets to the feed end of the boom.

In order to permit the printer-slotter to continue to operate and feed box blanks to the sheet stacker, the invention provides a group of hold-back slats which are mounted on the boom in the plane of the conveyor belts and intermixed among the feeding belts. These hold-back slats are pivotally mounted on the boom and are arranged to be raised manually at any position of the boom and to be raised automatically when the booms delivery end is in its uppermost sheet-delivering position. Means are also provided to automatically lower the raised ends of the hold-back slats when the delivery end of the boom is in its lowermost sheet-delivering position. The manual operation of the hold-back raising linkage permits the operator to continue operation of the printer-slotter and the boom conveyor belts while clearing a stoppage or other difficulty at the delivery end of the machine. If this were not possible, it would be necessary to stop the feed of the sheets to the machine and to shut down both the printer-slotter and the layboy and boom belts (a very costly procedure).

The layboy is, in the illustrated embodiment of the invention, afiixed to the frame at the feed end of the sheet stacker boom. The layboy belts are driven in the direction from the printer-slotter toward the sheet stacker so that the sheets fed to the layboy from the printer-slotter are delivered to the boom belts. The layboy is mounted to the frame so that the end nearer the printer-slotter may be raised mechanically to permit the operator to make adjustments of both the printer-slotter and the layboy. The belts of the layboy are mounted so that they may be moved transversely of the machine depending upon the size of the sheets being stacked. Hold-down straps are provided as a part of the layboy for positioning the sheets on the layboy belts. These hold-down straps may be moved transversely of the machine and held in position so as to overlay the plane of the layboy belts, either between the belts or directly above one or more of the belts. The straps are locked in the desired positions so that they do not drop down on or between the belts when the feed of sheets is interrupted or stopped.

In the drawings, wherein, for the purpose of illustration, is shown an embodiment of the invention, the numeral 10 designates the frame of the sheet stacker. The frame 10 is mounted on bases 11 (FIGURES l and 2A) and boom 12 is mounted within frame 11 (FIG- URE 1). Several parallel conveyor belts 14 are mounted on boom 12 and are driven by shaft 16 (FIGURES 2 and 4). Idler shaft 18 is provided for belts 14 at the delivery end of the boom 12 (FIGURES 1, 2A and 6). The sheets are stacked on pallet 20 which is placed in position at the delivery end of the machine and are aligned so as to form a neat pile on pallet 20 by a stack guiding means such as hopper 22.

Stack switch assembly 24 is provided at the delivery end of the boom to raise the delivery end of the boom a predetermined amount after a predetermined amount of sheets have been stacked onto pallet 26. Two remote control stations 26 (FIGURE 1) and 27 (FIGURE 2) are provided with the necessary control buttons to permit the operator to control the machine from either the feed end or the delivery end. Motor 28, which is used for raising the delivery end of the boom, and motor 30, which is used for lowering the delivery end of the boom, are connected to each other by means of belt 31 and are electrically wired to brake 29. Brake 2? is a solenoid type disc brake which opens when the motor is energized and closes when the motor is deenergized. Two belts 33 are connected from the pulley on the shaft of motor 28 to right angle, gear box 32 which changes the direction of the drive from the motors in order to actuate the movement of the chains 44 and 46 which are used to raise and lower the delivery end of the boom. Power is supplied from the mains to the various motor controls of the machine from transformer 37 which is mounted on frame 10.

The drive from gear box 32 to the vertical motion, drive shaft 38 is through sprockets 36 and 34 and chain 35. Sprockets 40 and 42 are mounted on shaft 38 and serve to control the motion of chains 44 and 46, respectively. Idler sprockets 48 and 5t engage chains 44 and 46, respectively and are positioned to keep the chains tight by means of take-up plates 52 and 54.

Belts 14 are driven by drive assembly 56 through shaft 16 (FIGURE 2). Chain 60 is driven by the sprocket on the shaft of motor 58 and is coupled to shaft 16; the details of the drive will be described later in this specification. Layboy 62 is mounted on bases 13 by means of pivot arms 69 (FIGURES 2, 4 and 5). Layboy 62 is mounted so that it pivots around drive shaft 66, pivots 71 and 71A (FIGURE 5). This permits the end of the layboy nearer the printer-slotter to be raised.

Layboy 62, which along with the feed end of the boom 12 is mounted on bases 13, is moved by the action of motor 78 and its associated parts (FIGURE 2). Support shaft 63 is suitably affixed to the pivot arms and thereby causes the layboy 62 to move when the pivot arms are moved. Motor 78 drives pinion 82 of FIGURE 2 and shaft 166 through chain 86. Shaft 169 drives a similar pinion for rack 84 of FIGURE 5. The motion of the pinions cause racks 84 to move up or down depending on the direction of rotation of the motor. The racks and pinions on both sides of the layboy are similar to each other and their motion is synchronized by means of shaft 16%. Rack 84 is held in position by means of roller guides 86. Rack 84 moves linkage arm 88 which is connected to pivot arm 69. Dog 91) is mounted on rack 84 and serves to contact the two limit switches 92 and 94. Switch 2 is the lower limit switch and serves to turn off motor 78 when the layboy is in its lowermost position and switch 94 is the upper limit switch and serves to turn off motor 78 when the layboy is in its uppermost position. Fixed arm 73 (FIGURE 5) is mounted on one side of the layboy and serves as a line of reference to which all the other elements of the layboy are related.

Each belt 64 is mounted on pulleys (details not shown) whose shafts are afiixed to a support arm 67 and is driven from shaft 66. The individual belt drives are keyed to shaft 66 which is provided with a groove which mates with the keys on the individual belt drives (details not shown). This type of mounting permits the belts 64 to be movable transversely along the drive shaft 66 and to be placed in position easily. Hold-down strap mounting rail 63 is held in position by support bracket 75 (FIGURES 2 and 4) and support bracket 77 (FIG- URE 5). The belt 64 nearest the side of the machine shown in FIGURE 2 is movable transversely and is equipped with locking adjustment 76 which is tightened when the belt is in the desired position. All the other belts in the layboy are movable but they are free at the end nearer the printer-slotter 74 and are not mechanically connected to mounting rail 63. Support brackets 65 are provided for each belt 64 and are placed around support shaft 63 so that the belts will not fall over toward the boom when the layboy is raised.

Hold-down straps 70 are formed of a rigid material such as thin strips of steel and are held in position along mounting rail 68 by means of screws 72. The hold-down straps are transversely movable across the layboy and may be put in the best position to act on the sheets being delivered to the layboy from priuter-slotter 74. The hold-down straps will not fall down on or between the belts when the feed of sheets stops because they are held in position by the adjustment screws 72.

Both sets of belts are driven from two-speed, varidrive motor 58. The speed of the vari-drive motor is varied by adjusting the positions of its pulleys by remote control in a manner well-known in the art (details not shown). Chain 60 drives sprockets 96 (FIGURE 4) which is mounted on shaft 16. This drives belts 14 and sprocket 98 which is suitably coupled to sprocket 1439 which is mounted on shaft 66. This shaft drives belts 64. The details of this drive mechanism will be described further on in this specification.

Hopper 22 (FIGURES 2A, 3 and 6) is seen to comprise guides 1G2, side rails 1154 and support 106. Guides 102 are transversely movable along support 106 depending upon the size of the sheet being processed. Side rails 104 are longitudinally movable to move support 106 nearer to or further away from the delivery end of boom 12. This adjustment is provided to permit the machine to handle sheets of difierent sizes. Guide 108 is provided to prevent the sheets from being thrown through the end of hopper 22. Guides 1118 (FIGURE 1) and 1112 are movable transversely across the width of the hopper and are locked to support 106 by means of adjustment screws 107.

Guide rollers 112 are provided On both sides of frame 19 (FIGURES 1 and 2A) to keep the boom in the correct position as it moves upwards. Chain adapter blocks 11% and 111 are mounted on boom 12 and are engaged in chains 44 and 46, respectively. It can thus be seen that the vertical movement of the delivery end of the boom is determined by the vertical movement of chains 44 and 46. I

Mounting bar 152 is affixed to boom 12 (FIGURE 6). Each slat 114 is hinged at bar 152 by means' of a hinge 154 to permit the ends of the slats nearer to the delivery end to be raised. Shaft 15 0 is provided as a rest for slats 114 to prevent them from dropping down too far below the level of the belts. The slats are covered with a rough belting material andwhen they are raised, they serve to hold back the flow of sheets to the hopper. This permits the operator to correct the stack, to remove a filled pallet, or to make other adjustments, such as repositioning a pallet to receive a second stack alongside a completed stack, without cutting off the flow of sheets from the printer-slotter. The slats 114 are situated generally in the plane of the belts 14 and are intermixed among the belts. Slats 114 may be moved both manually and automatically as will appear as. this description proceeds.

Linkage 116 is coupled to shaft 122 on which are mounted rocker-lifters 120. There is a rocker-lifter 12% mounted under eachslat 114. Handle 118 is connected to linkage 116 and when moved in either direction from that shown in FIGURE 2A, it causes the rockerlifters 120 to move and raise the free ends of slats 114. This manual raising of the ends of the slats may be accomplished at any position of the boom 12. Linkage pin 124 is employed to provide automatic raising and lowering of the slots. Pin 124 is placed so that it will be acted upon by dog 128 at theuppermost point of travel of the delivery end of boom 12 and by dog 126 at the lowermost point of travel of the delivery end of boom 12. Both the dogs are mounted on frame 10 (FIG- URE 2A). 7

Limit switches 130, 132, 134 and 136 are mounted on frame 10 (FIGURE 2A). These switches are engageable (capable of being'engaged) by a lever arm afiixed to the boom 12 (details not shown). While it is possible to use a single lever arm to accomplish this purpose, in the embodiment illustrated two lever arms afiixed to the boomare used. Switches139 and 132 are engageable by one lever arm and switches 134 and 136 are engageable by the other lever arm.

Switch 130 is the maximum lower limit switch and stops the downward motion of the boom. Switch 132 is actuated as the boom is descending and performs two functions: it actuates the dynamic brake system and switches the belt drive motor 58 from low speed to high speed. Switch 134 is actuated on the ascent of the boom and performs two functions; it switches the belt drive motor 58 from high speed to low speed and engages motor 28 to raise the boom constantly to permit the bottom of hopper 22 to clear the stack of sheets on the pallet. Switch 136 is actuated on ascent and stops the upward motion of the boom.

The tensions of the chain which are employed to raise and lower the boom are adjusted by means of chain takeup plates 52 and 54. Both these takeup plates are operated in the same manner. The structure of takeup plate 52 is illustrated in FIGURE 2A. Slots 140 are provided in the plate and studs 142, WhlCh fit in slots 140, are mounted on the frame 10. The adjustment 15 made by means of screw 138 which is engaged by a threaded stud in frame 10. The studs 142 are then tightened to hold the assembly in place.

In FIGURE 3 there is illustrated the means for controlling the upward vertical motion of the delivery end of the boom as the sheets are piled on the pallet. Stack switch assembly 24 is mounted on the end or" the boom as shown in FIGURE 1. It comprises stack switch 144, pressure strip 148 and switch arm 146. As the sheets come oif the delivery end of the boom, they contact pressure strip 148 which acts against switch arm 146. A time delay mechanism, which is mounted in the electrical panel, is associated with switch assembly 24. It serves to keep the motor 28 from being energized by the action of single sheets making contact with pressure strip 148. After a sufiicient number of sheets have been stacked on the pallet, there is continued pressure on strip 148 which closes switch 144 for enough time to overcome the time delay and cause motor 28 to turn ON. The boom is then raised by motor 28 and the associated drive chains. The second time delay portion of the circuit (also mounted in the panel) comes into operation to continue to keep motor 28 running for the period of time necessary to raise the delivery end of the boom sufliciently, usually in increments of about 4 inches. This permits the stacking of sheets on the pallet without requiring the motor 28 to be operated too frequently.

In FIGURES 7 and 8 there is illustrated the detailed structure of the floating link which is used in the drive system for the belts. Motor 58 drives sprocket 96 through chain 58 to drive shaft 16 to which are coupled the boom belts 14. Sprocket 98 is also mounted on shaft 16 and it drives coupling sprocket 158 through chain 162. Coupling sprocket 158 is mounted on knee action pivot 156 which moves from the position shown in the solid lines of FIGURE 7 to that shown in the dotted lines in the figure. Coupling sprocket 158 drives layboy belt drive sprocket 1% through chain 164. Sprocket 180 is mounted on shaft 56 which is the drive shaft for belts 64.

As the delivery end of the boom rises, roller 166, which is afiiXed to the boom 12, moves forward along frame 10. When the delivery end of the boom is in its uppermost position, roller 166 is in the position shown dotted in FIGURE 7. As the feed end of boom 12 moves toward the delivery end due to the vertical rise of the delivery end, pivot 156 moves forward and up and shaft 16 moves forward. The layboy is afiixed to shaft 65 which does not change its position. Thus it can be seen that the layboy does not change its position with respect to the printer-slotter. Since the machine is designed so that feed ends of the boom belts 14 are actually under the delivery ends of the layboy belts 64 when the boom is in both its lowermost position and its uppermost position, the sheets move smoothly from the layboy belts to the boom belts.

The operation of the sheet stacker illustrated in FIGURES 1 through 8 proceeds as follows: the layboy belts are adjusted so that the particular size sheets delivered from the printer-slotter 74 are supported by at least two of the belts with sufiicient spacing to prevent sagging of the sheets in their centers or at their ends. The hold-down straps 79 are set and locked in position so that they will deflect the sheets onto the belts and hold them down on the belts as they are delivered from the printer-slotter 74. Next, the layboy is lowered into receiving position.

A pallet 28 is placed under hopper 22 and the hopper is adjusted for the size sheet being stacked by adjusting the guides 102 and the side rails 104. The belts of the sheet stacker are started. Then the printer-slotter is started and the sheets are delivered from the printerstarter against the hold-down straps. The hold-down straps force the sheets down so that they rest flat on the belts 64. The sheets are carried by belts 64 onto belts 14 toward the hopper. As the sheets leave the belts 14 they are pushed against guides 102 and oriented in position as they drop onto the pallet. As the pile grows, the sheets on the pallet start to press against pressure strip 148. As sheets are added the pressure becomes great enough on arm 146 to close switch 144 for a suflicient period of time. When switch 144 is so closed, motor 28 is turned ON and the boom starts to rise. In order to allow the boom to rise a predetermined amount, a time delay relay is included as a part of the switching system. The time delay relay keeps the circuit to the motor closed for the required period of time to permit the boom to rise in increments of about four inches.

This operation repeats itself until the lever on the boom makes contact with switch 134 and linkage pin 124- contacts dog 128. The engagement of the linkage pin and the dog raises the hold-back slats and prevents the sheets from being delivered from the end of the boom. The switch 134 turns on the power to motor 28 and bypasses switch 144 to raise the boom at a constant rate so that the hopper clears the top of the stack on the pallet. Switch 134 also switches belt drive motor 58 from high speed to low speed. This permits the sheets to continue to be fed from the printer-slotter in a more even distribution over the layboy and boom. The boom continues to rise until the lever contacts switch 136 which turns off motor 28 and stops the upward motion of the boom.

The pallet is now moved away, either automatically or manually, and a new pallet is moved into place under the hopper. Under certain conditions, the pallet may be used to accomodate two or more piles of sheets. In such cases, the pallet is repositioned to receive the second stack and is removed when all stacks are piled upon it. Now, the operator pushes the DOWN button located at either of the remote stations 25 or 27. This actuates motor 30 and the boom descends at high speed until the lever on the boom hits switch 132 and linkage pin 124 hits dog 126.

Switch 132 actuates the dynamic brake system and switches belt drive motor 58 from low speed to high speed. The action of dog 126 on linkage pin 128 causes the hold-back slats to drop and permits the sheets to be delivered from the boom to the pallet. The dynamic brake operates in the manner which is wellknown in the art. Motor 28 is a 2 H.P., 1200 r.p.m. motor and is coupled at a 1:3 pulley ratio to motor 30 which is a H.P., 1800 r.p.m. motor. When the boom is rising, motor 28 tows motor 30 at about 600 r.p.m. which has little or no effect on the operation. When the boom is being lowered, motor 30 tows motor 28 at about 5400 r.p.m. until it arrives a short distance (about 4 inches) above the normal stopping point. The motor 30 is switched off and motor 28 is switched on. Motor 28 tends to move at its normal rotational velocity (1200 r.p.m.). Since this is much lower than that at which it was being towed (5400 r.p.m.), it serves to arrest the downward vertical movement of the boom and in conjunction with the action of brake 29, which is energized when motor 28 is turned off by switch 130, to bring the boom to a smooth stop.

The boom continues to descend until the lever actuates switch 130. Switch 130 turns olf motor 28 and puts the electrical circuit in condition for the switch 144 to actuate the raising motor 28.

If at any time during the run, the operator must stop the feed of sheets to the pallet, he may do so by raising the holdback slats manually. This is done by operating handle 118. As soon as the difiiculty has been cleared,

the slats are dropped by the reverse manual operation of handle 118.

While particular embodiments have been shown and described, it is apparent to those skilled in the art that modifications are possible without departing from the spirit and scope of the invention.

Having thus described the invention, we claim:

1. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printer-slotter onto a pallet comprising:

a frame;

a boom mounted in the frame;

the boom being movable with respect to the frame such that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a plurality of parallel, movable belts mounted on the boom so as to move from the feed end toward the delivery end;

at least one slat pivotally mounted in the plane of the plurality of movable belts such that the end of the slat nearer the delivery end may be raised with respect to the plane of the plurality of movable belts;

means for moving the plurality of movable belts in synchronisrn;

means for raising the delivery end of the boom vertically upwards;

means for lowering the delivery end of the boom vertically downwards;

means for automatically raising the end of the slat nearer the delivery end when the boom is in its uppermost position;

means for automatically lowering the raised end of the slat when the boom is in its lowermost position;

means for manually raising and lowering the end of the slat nearer the delivery end at any position of the boom;

means for guiding the sheets into a stack on the pallet;

and

means for automatically actuating the boom raising means such that the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet.

2. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printer-slotter onto a pallet comprising:

a frame;

a boom mounted in the frame; a

the boom being movable with respect to the frame such that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a plurality of parallel, movable belts mounted on the boom so as to move from the feed end toward the delivery end;

a plurality of slats pivotally mounted and intermixed between the belts of the plurality of movable belts and in the plane thereof such that the ends of the slats nearer the delivery end may be raised with respect to the plane of the plurality of movable belts;

means for moving the plurality of movable belts in synchronism;

means for raising the delivery end of the boom vertically upwards;

means for lowering the delivery end of the boom vertically downwards;

means for automatically raising the ends of the slats nearer the delivery end when the boom is in its uppermost position;

means for automatically lowering the raised ends of the slats when the boom is in its lowermost position;

means for manually raising and lowering the ends of the slats nearer the delivery end at any position of the boom;

means for guiding the sheets into a stack on the pallet;

and

means for automatically actuating the boom raising means such that the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet.

3. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printer-slotter onto a pallet comprising:

a frame;

a boom mounted in the frame;

the boom being movable with respect to the frame such that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a first plurality of parallel movable belts mounted on the boom so as to move from the feed end toward the delivery end;

at least one slat pivotally mounted in the plane of the first plurality of movable belts such that the end of the slat nearer the delivery end may be raised with respect to the plane of the first plurality of movable belts;

means for moving the first plurality of movable belts in synchronism;

means for raising the delivery end of the boom vertically upwards;

means for lowering the delivery end of the boom vertically downwards;

means for automatically raising the end of the slat nearer the delivery end when the boom is in its uppermost position;

means for automatically lowering the raised end of the slat when the boom is in its lowermost position;

means for manually raising and lowering the end of the slat nearer the delivery end of the boom at any position of the boom;

means for guiding the sheets into a stack on the pallet;

means for automatically actuating the boom raising means such that the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet;

a layboy aflixed to the frame between the feed end and the printer-slotter;

said layboy comprising:

a second plurality of movable belts mounted so as to move from the printer-slotter end toward the delivery end;

a mounting bar affixed to said layboy adjacent to the printer-slotter;

at least one hold-down strap mounted on said mounting bar and movable therealong;

said hold-down strap being shaped so as to overlay the plane of said second plurality of movable belts;

means for moving said second plurality of belts in synchronism; and

motor means for raising and lowering the end of the layboy adjacent to the printer-slotter.

4. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printerslotter onto a pallet comprising:

a frame;

a boom mounted in the frame;

the boom being movable with respect to the frame such that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a first plurality of parallel movable belts mounted on the boom so as to move from the feed end toward the delivery end;

a plurality of slats pivotally mounted and intermixed between the belts of the first plurality of movable belts and in the plane thereof such that the ends of the slats nearer the delivery end may be raised with 9 respect to the plane of the first plurality of movable belts;

means for moving the first plurality of movable belts in synchronism;

means for raising the delivery end of the boom vertically upwards;

means for lowering the delivery end of the boom vertically downwards;

means for automatically raising the ends of the slats nearer the delivery end when the boom is in its uppermost position;

means for automatically lowering the raised ends of the slats when the boom is in its lowermost position;

means for manually raising and lowering the ends of the slats nearer the delivery end at any position of the boom;

means for guiding the sheets into a stack on the pallet;

means for automatically actuating the boom raising means such that the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet;

a layboy afixed to the frame between the feed end and the printer-slotter;

said layboy comprising:

a second plurality of movable belts mounted so as to move from the printer-slotter end toward the delivery end;

a mounting bar affixed to said layboy adjacent to the printer-slotter;

a plurality of hold-down straps mounted on said mounting bar and movable therealong;

said hold-down straps being shaped so as to overlay the plane of said second plurality of movable belts;

means for moving said second plurality of movable belts in synchronism; and

motor means for raising and lowering the end of said layboy adjacent the printer-slotter.

5. A sheet stacker as described in claim 3 wherein the motions of said first plurality of movable belts and said second plurality of movable belts are synchronized.

6. A sheet stacker as described in claim 4 wherein the motions of said first plurality of movable belts and said third plurality of movable belts are synchronized.

7. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printer-slotter onto a pallet comprising:

a frame;

a boom mounted in the frame;

the boom being movable with respect to the frame such that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a plurality of parallel movable belts mounted on the boom so as to move from the feed end toward the delivery end;

a plurality of slats pivotally mounted and intermixed between the belts of the plurality of movable belts and in the plane thereof such that the ends of the slats nearer the delivery end may be raised with respect to the plane of the plurality of movable belts;

a drive shaft mounted at the feed end of the boom and adapted to drive the plurality of movable belts in synchronism;

a first motor coupled to the drive shaft;

a pair of movable chains mounted vertically in the frame, one at each side of the delivery end of the frame;

a pair of chain adapter blocks mounted to the boom, one at each side of the delivery end, and cooperatively engaging each chain;

a second motor for lowering the boom and a third motor for raising the boom connected in a dynamic brake brake circuit so as to move the pair of chains in both directions to raise and lower the delivery end of the boom;

a plurality of rocker lif.ers mounted on the boom under the plurality of slats;

a lifting linkage mounted on the boom at the delivery end coupled to the plurality of rocker lifters;

a handle adapted to move the lifting linkage so as to raise the ends of the slats nearer the delivery end at any position of the boom;

a pair of dogs mounted on one side of the delivery end of the frame near the top and bottom thereof adapted to engage the lifting linkage so as to raise the ends of the slats nearer the delivery end when the boom is in its uppermost position and to lower the raised ends of the slats when the boom is in its lowermost position;

means for guiding the sheets into a stack on the pallet;

and

a switch mounted on the delivery end of the boom and a relay connected to the switch adapted to be actuated by the sheets delivered by the belts onto the pallet such that the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet.

8. A sheet stacker as described in claim 7 including:

a layboy affixed to the frame between the feed end and the printer-slotter;

said layboy comprising:

a second plurality of movable belts mounted so as to move from the printer-slotter and toward the delivery end;

a mounting bar aifixed to the layboy adjacent to the printer-slotter;

a plurality of hold-down straps mounted on said mounting bar and movable therealong;

said hold-down straps being shaped so as to overlay the plane of the second plurality of movable belts;

a second drive shaft mounted in the layboy adjacent to the feed end of the boom and adapted to drive the third plurality of movable belts;

means for coupling the first motor to the second drive shaft such that the second plurality of movable belts is moved in synchronism with the first plurality of movable belts; and

a fourth motor for raising and lowering the end of the layboy adjacent the printer-slotter.

9. A sheet stacker as described in claim 8 wherein:

said first motor is a two speed motor; and including at least one lever arm mounted on the boom at the delivery end;

a pair of switches mounted on the delivery end of the frame, one near the bottom and one near the top, and adapted to be engaged by the lever arm such that the first motor is switched from high to low speed near the top of the travel of the boom and is switched from low to high speed near the bottom of the travel of the boom.

10. A sheet stacker as described in claim 7 wherein:

said first motor is a two speed motor; and including at least one lever arm mounted on the boom at the delivery end;

a pair of switches mounted on the delivery end of the frame, one near the bottom and one near the top, and adapted to be engaged by the lever arm such that the first motor is switched from high to low speed near the top of the travel of the boom and is switched from low to high speed near the bottom of the travel of the boom.

11. A sheet stacker having a feed end and a delivery end for feeding sheets to be stacked from a printer-slotter onto a pallet comprising:

a frame;

a boom mounted in the frame;

the boom being movable with respect to the frame such 1 1 that the delivery end is movable vertically and the feed end moves horizontally to compensate for the vertical movement of the delivery end;

a plurality of parallel movable belts mounted on the 12 move from the printer-slotter end toward the delivery end; a mounting bar aflixed to the layboy adjacent to the printer-slotter;

boom so as to move from the feed end toward the 5 a plurality of hold-down straps mounted on the mountdelivery end; ing bar and movable therealong;

a plurality of slats pivotally mounted and intermixed said hold-down straps being shaped so as to overlay between the belts of the plurality of movable belts the plane of the second plurality of movable belts; and in the plane thereof such that the ends of the slats a second drive shaft mounted in the layboy adjacent to nearer the delivery end may be raised with respect to the feed end of the boom and adapted to drive the the plane of the plurality of movable belts; third plurality of movable belts;

a drive shaft mounted at the feed end of the boom means for coupling the first motor to the second drive and adapted to drive the plurality of movable belts shaft such that the second plurality of movable belts in synchronism; is moved in synchronism with the first plurality of a first motor coupled to the drive shaft; movable belts; and

a pair of movable chains mounted vertically in the a fourth motor for raising and lowering the end of the frame, one at each side of the delivery end of the layboy adjacent to the printer-slotter. f 14. A sheet stacker as described in claim 13 wherein:

a pair of chain adapter blocks mounted to the boom, the first motor is a two speed motor and is switched one at each side of the delivery end, and cooperatively from low speed to high speed when the second switch engaging h h in; is actuated by the lever and is switched from high a second motor for lowering the boom and a third motor speed to low speed when the third switch is actuated for raising the boom connected in a dynamic brake by the lever. circuit so as to move the pair of chains in both direc- 15. A sheet stacker having a feed end and a delivery tions to raise and lower the delivery end of the boom; end for feeding sheets to be stacked from a printer-slotter a plurality of rocker lifters mounted on the boom onto a pallet comprising:

under the plurality of slats; a frame;

a lifting linkage mounted on the boom at the delivery a boom mounted in the frame;

end coupled to the plurality of rocker lifters; the boom being movable with respect to the frame a handle adapted to move the lifting linkage so as to such that the delivery end is movable vertically and raise the ends of the slats nearer the delivery end at the feed end moves horizontally to com ensate for any position of the boom; the vertical movement of the delivery end;

a pair of dogs mounted on one side of the delivery end a first plurality of parallel movable belts mounted on of the frame near the top and bottom thereof adapted the boom so as to move from the feed end toward to engage the lifting linkage so as to raise the ends the delivery end; of the slats nearer the delivery end when the boom a plurality of slats pivotally mounted and interis in its uppermost position and to lower the raised mixed between the belts of the first plurality of ends of the slats when the boom is in its lowermost movable belts and in the plane thereof such that the iti ends of the slats nearer the delivery end may be t l t one l v o nted on the boom t the raised with respect to the plane of the first plurality of movable belts;

first drive shaft mounted at the feed end of the boom and adapted to drive the first plurality of movable belts in synchronism;

first, two-speed motor coupled to the first drive shaft;

pair of movable chains mounted vertically in the frame, one at each side of the delivery end of the frame;

near the top thereof and engageable by the lever arm a pair of chain adapter blocks mounted to the boom,

to actuate the third motor to raise the boom; one at each side of the delivery end, and cooperaa fourth switch mounted on the delivery end of the tively engaging each chain;

frame near the top thereof and above the third switch a Second motor for lowering the boom and a third moand engageable by the lever arm to stop the ascent tor for raising the boom connected in a dynamic of the boom; brake circuit so as to move the pair of chains in both directions to raise and lower the boom; plurality of rocker lifters mounted on the boom under the plurality of slats;

a lifting linkage mounted on the boom at the delivery means for guiding the sheets into a stack on the pallet;

and a a fifth switch mounted on the delivery end of the boom and a relay connected to the switch adapted to be actuated by the sheets delivered by the belts into the end coupled to the plurality f rocker lifters; pallet Such that the delivery end of the boom is a handle adapted to move the lifting linkage so as to raised a predetermined amount when a predetermined false ends of the slats nearer the ehvery end at amount of sheets have been stacked onto the pallet. y Posmon of the boom; 12. A sheet stacker as described in claim 11 wherein: a pair of dogs mounted on one slde of the dehvery end the first motor is a two speed motor and is switched of the frame near he and bottom ther-eof adapted from low speed to high speed when the second switch g the hflmg lmka-ge so as to false the ends is actuated by the lever and is switched from high 9 e? s ats nearer the Fhvery end when the bqom speed to low speed when the third switch is actuated 1S In Its uppermost Posmon and t9 I-OWH the reused ends of the slats when the boom 1s in its lowermost by the lever. position;

13. A sheet stacker as described in claim 11 including:

a layboy affixed to the frame between the feed end and the printer-slotter;

said layboy comprising: a

a second plurality of movable betls mounted so as to a first switch mounted on the delivery end of the frame near the bottom thereof and engageable by the lever arm to stop the downward movement of the boom; second switch mounted on the delivery end of the frame near the bottom thereof and above the first a fourth switch mounted on the delivery end of the frame near the top thereof and above the third switch and engageable by the lever arm to stop the ascent of the boom;

means for guiding the sheets into a stack on the pallet; a fifth switch and a relay mounted on the delivery end of the boom adapted to be actuated by the sheets delivered by the belts onto the pallet such that the third motor is actuated and the delivery end of the boom is raised a predetermined amount when a predetermined amount of sheets have been stacked onto the pallet;

a sixth switch adapted to be operated manually to start the second motor at high speed to cause the boom to descend from its uppermost position;

a layboy aihxed to the frame between the feed end and the printer-slotter;

said layboy comprising:

a second plurality of movable belts mounted so as to move from the printer-slotter end toward the delivery end;

a mounting bax afixed to the layboy adjacent to the printer-slotter;

a plurality of hold-down straps mounted on the mounting bar and movable therealong;

said hold-down straps being shaped so as to overlay the plane of the second plurality of movable belts;

a second drive shaft mounted in the layboy adjacent to the feed end and adapted to drive the second plurality of movable belts;

means for coupling the first motor to the second drive shaft such that the second plurality of movable belts is moved in synchronism with the first plurality of movable belts;

a fourth motor for raising and lowering the end of the layboy adjacent to the printer-slotter; and means for limiting the amount which the end of the layboy adjacent the printer-slotter is raised and lowered.

16. A layboy for delivering sheets from a printerslotter to a sheet stacker comprising:

a frame;

a plurality of movable belts mounted so as to move from the printer-slotter toward the sheet stacker;

a mounting bar atfixed to the layboy adjacent to the printer-slotter;

at least one hold-down strap mounted on the mounting bar and movable therealong;

a drive shaft mounted to the frame and adapted to drive the plurality of movable belts;

driving means coupled to the drive shaft; and

a motor for raising and lowering the end of the layboy adjacent to the printer-slotter.

17. A layboy for delivering sheets from a printerslotter to a sheet stacker comprising:

a frame;

a plurality of movable belts mounted so as to move from the printer-slotter toward the sheet stacker;

a mounting bar aflixed to the layboy adjacent to the printer-slotter;

a plurality of hold-down straps mounted on the mounting bar and movable therealong;

a drive shaft mounted to the frame and adapted to drive the plurality of movable belts;

driving means coupled to the drive shaft;

a motor for raising and lowering the end of the layboy adjacent to the printer-slotter; and

means for limiting the amount which the end of the layboy adjacent to the printer-slotter is raised and lowered.

References Cited in the file of this patent UNITED STATES PATENTS Wood Nov. 23, 1897 Seft July 16, 1940 

16. A LAYBOY FOR DELIVERING SHEETS FROM A PRINTERSLOTTER TO A SHEET STACKER COMPRISING: A FRAME; A PLURALITY OF MOVABLE BELTS MOUNTED SO AS TO MOVE FROM THE PRINTER-SLOTTER TOWARD THE SHEET STACKER; A MOUNTING BAR AFFIXED TO THE LAYBOY ADJACENT TO THE PRINTER-SLOTTER; AT LEAST ONE HOLD-DOWN STRAP MOUNTED ON THE MOUNTING BAR AND MOVABLE THEREALONG; A DRIVE SHAFT MOUNTED TO THE FRAME AND ADAPTED TO DRIVE THE PLURALITY OF MOVABLE BELTS; DRIVING MEANS COUPLED TO THE DRIVE SHAFT; AND A MOTOR FOR RAISING AND LOWERING THE END OF THE LAYBOY ADJACENT TO THE PRINTER-SLOTTER. 